Transcript for Newtown Shooting Stories of Bravery, Teachers Rise Up to Face Gunman

I want to go to josh elliott who has the stories of so many who did the right thing in the hardest circumstances. Josh? I'm standing outside a church where all those lost yesterday were remembered. And they will now be permanent scars for this community. But to your point, there are so many inspiring tales of heroism, for all of those teachers who put their own safety at risk, to protect their students, to the students themselves. So composed in the face of such unimaginable horror. Here are their stories. Amid the anguish and tragedy and agony of the shooting at sandy hook elementary, were incredible acts of heroism. I thought we were all going to die. Reporter: First grade teacher kaitlin roig told diane sawyer, she put her class in a bathroom. We have to be absolutely quiet. There are bad guys out there now. We have to wait for the good guys. Reporter: Down the hall, the third grade class heard the gunshots over the school's intercom. She locked the door. And put a piece of white tape over the window of the door. And she told us to go in the corner. Reporter: Pregnant and due with a baby any day, she tried to keep her class calm. We kept hearing gun noises. And put your hands up. And we just kept hearing that. Reporter: What is she saying to you? She is just saying, it's going to be okay. Just be quiet. Reporter: Were your friends and classmas doing at this point? We were in the corner, all crouched in. And all the girls were trying. A couple of boys. And the boysere like, they had their eyes wide-open, watching everything. Did you hear your principal say anything? Yeah. She was crying. And I thought she was screaming. That's what we heard over the loud speaker. We heard kids crying. Reporter: While parents rushed to the school, desperate to find their children. As a parent, what must those moments have been like? It's horrifying. You always worry about your kids. But it's something that you can never think would actually ever happen. You never really are prepared. Reporter: Do you worry about going back to school? Yeah. I don't want to. Reporter: What do you want to say to her? I want to thank you for saving my life. There are 19 people in our class. And she saved all of us. Now, there were so many discussions on social media yesterday, about the proprietity of talking to the children of this tragedy. As our dr. Besser says about a tragedy such as this, it's more important to know your child. And to that end, little tori's parents wanted her to talk about this. And one final note of heroism, dawn hochsprung, the principal that was killed in the attack, did manage to turn on the intercom before that happened. It is believed that this was a final act of heroism on her part to warn the teachers and students of what was to come.

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